Magnetic separator



1960 c. w. v. DAVIS EI'AL 2,959,287

MAGNETIC SEFARATOR Filed Jan. 29, 1957 2 Sheets-Sheet 1 FIGJ g 4 L a i & 9 9 1 J 8 1 I I fin n 'n-\ 11;! I l I 8 I r'll F" mun Mill [tit M f I -4" i F1] r nmn mun LE1 -J INVENTORS CHARLES WILLIAM VERITY DAVIS WILLIAM OMRLES CLNJE WESTVDOD';

AGE

Nov. 8, 1960 c. w. v. DAVIS 'ET AL 2,959,287

MAGNETIC SEPARATOR Filed Jan. 29, 1957 2 Sheets-Sheet 2 7/ lAr/////// r/ 7/ 7/4/7 v I, II. I I

FIG

INVENTORS CHARLES WILLIAM VERITY DAVIS WILLIAM CHARLES cLAuoE WESTWOOQ 124.1. K AGE T MAGNETIC SEPARATOR Charles William Verity Davis, Arkley, Barnet, and William Charles Claude Westwood, Bexley, England, assignors, by mesne assignments, to North American Philips Company, Inc., New York, N.Y., a corporation of Delaware Filed Jan. 29, 1957, Ser. No. 636,990

Claims priority, application Great Britain Mar. 19, 1956 2 Claims. (Cl. 210-222) The invention relates to magnetic separators for the removal from a fluid which is passed through the separator of magnetizable particles contained in the fluid and is concerned with that type of separator which oomprises a plurality of coaxial filter elements mounted on a central magnetic core and a pole piece being provided at each end of the stack or pile.

According to the invention, a filter element for a magnetic separator of the type specified comprises a plate of term-magnetic material formed with a plurality of rows of slots and is provided along at least one edge of each slot with a wall portion extending in a direction perpendicular to the plane of the filter element. Preferably, each of the said wall portions is formed, as the result of a pressing operation, by the material removed from the slot. For example, the arrangement may be such that the surface of the plate is out to form three sides of a slot and is then bent along the fourth side so as to form a wall extending along the uncut side of the slot. Preferably also, the plate is substantially circular and is formed with concentric, circular, rows of arcuate slots.

The invention will now be described with reference to the embodiments shown in the accompanying drawings in which:

Figure 1 is a side view, partly in section, of a magnetic separator according to the invention,

Figure 2 is a plan view of a portion of a filter element,

Fig. 3 is a sectional view showing a portion of a separator provided with filter elements of a modified form; and

Fig. 4 is a sectional view showing a portion of a separator provided with filter elements of a further modified form.

Referring to Figures 1 and 2 of the drawings, a magnetic separator comprises a hollow non-magnetic casing 1 of substantially cylindrical shape within which is housed a core 2 comprising a permanent magnet of bar form or a permanent magnet assembly composed of more than one magnet. At each end of the casing 1 is provided a pole piece 4 and the complete assembly is held together by means of a central bolt 3.

Filter elements 5 are carried by the casing 1 and each filter element comprises a substantially disc-shaped plate of ferro-magnetic material, e.g. soft iron, having formed therein a central aperture 6 to accommodate the casing 1 and core 2, together with several circular, concentric rows of arcuate slots 7, each slot being provided along its inner edge with a wall 8 which extends perpendicular its States Patent 0 to the plane of the plate and which is formed by material which has been pressed upward out of the surface of the plate when forming the slot.

In order to maintain the filter elements in spaced relationship, spacing pins 9 of non-magnetic material are secured to each element adjacent the periphery of the element. In a modification, shown in Figure 3, the slots of the inner row are wider than those of the other rows, thus providing arcuate walls 11 which extend further than the walls 8 and abut against the underside of the superposed element. In a further modification, Figure 4, the edge of the central aperture 6 of each element is provided with a rim portion 10 which is formed from material from the centre of the plate and which extends upwardly, parallel to the wall portions 8, and acts as a spacing member: the rim portion 10 may be formed as a continuous wall or alternatively may be formed as a number of separate wall portions similar to the wall portions 11 shown in Fig. 3.

In a further modification, instead of only one arcuate edge of each slot being provided with a wall, both arcuate edges may have walls, each wall being formed in a manner similar to that described above. In this modification all slots may be of the same width, the slots of the inner row each having associated therewith a single wall which acts as a spacing member in a similar manner to the Walls 11 in Figure 3, while the slots of the remaining rows have, associated with each slot, two walls of approximately half the height of the walls associate-d with the inner row of slots.

In operation, the magnetic separator is enclosed in a casing 12 having an inlet 13 and an outlet 14 for the fluid.

What is claimed is:

1. A filter for a magnetic separator comprising a hollow support member, a plurality of superposed, spaced plates mounted on said hollow support member and having a plurality of slots therein, a plurality of upstanding walls substantially perpendicular to the plane of said plates and being struck-out of said plates to form said slots, said slots being in concentric rows and each of the slots of the inner row being wider than the slots in the other rows, each slot of said inner row being provided along its inner edge with an upstanding wall extending further than the upstanding walls of the other rows of slots and abutting the underside of the plate located directly above a central casing supporting said spaced plates having a permanent magnet therein and provided with an inlet and outlet, and pole pieces mounted on opposite ends of said casing.

2. A filter for a magnetic separator as claimed in claim 1 wherein said inner row is formed from material pressed from said hollow support member.

References Cited in the; file of this patent UNITED STATES PATENTS 1,602,935 Rasey Oct. 12, 1926 1,977,174 Crawford Get. 16, 1934 2,149,764 Frei Mar. 7, 1939 2,436,108 Heftler Feb. 17, 1948 FOREIGN PATENTS 697,826 Germany Oct. 24, 1940 

